A climatological model of the equatorial electrojet based on Swarm satellite magnetic intensity observations

The Equatorial Electrojet (EEJ) is a spatially localized electric current in the ionospheric dynamo region, flowing along the magnetic dip equator at an altitude of about 110 km, mainly on the dayside. Previous empirical models of the EEJ were based on magnetic intensity observations from the Ørsted, CHAMP, and SAC-C satellites. However, with the launch of the Swarm satellite trio in November 2013, a considerable amount of new data is available. We use latitudinal profiles of EEJ sheet current densities based on magnetic intensity measurements of the Swarm A and B satellites to construct a climatological model of the EEJ. This model describes sheet current density variations with local time, longitude, season, lunar phase, and the F 10.7 solar flux. We validate our model with independent EEJ current density estimates from the Swarm C and CSES satellites.